diff --git a/include/lua/bitmap.hpp b/include/lua/bitmap.hpp
index 4a6c05fc..1c679cad 100644
--- a/include/lua/bitmap.hpp
+++ b/include/lua/bitmap.hpp
@@ -61,6 +61,7 @@ struct lua_bitmap
 	template<bool scaled> int blit_priority(lua::state& L, lua::parameters& P);
 	int save_png(lua::state& L, lua::parameters& P);
 	int _save_png(lua::state& L, lua::parameters& P, bool is_method);
+	int sample_texture(lua::state& L, lua::parameters& P);
 };
 
 struct lua_dbitmap
@@ -85,6 +86,7 @@ struct lua_dbitmap
 	int save_png(lua::state& L, lua::parameters& P);
 	int adjust_transparency(lua::state& L, lua::parameters& P);
 	int _save_png(lua::state& L, lua::parameters& P, bool is_method);
+	int sample_texture(lua::state& L, lua::parameters& P);
 };
 
 struct lua_loaded_bitmap
diff --git a/lua.lyx b/lua.lyx
index bdebfc71..dd31c96d 100644
--- a/lua.lyx
+++ b/lua.lyx
@@ -1,7 +1,9 @@
-#LyX 2.1 created this file. For more info see http://www.lyx.org/
-\lyxformat 474
+#LyX 2.2 created this file. For more info see http://www.lyx.org/
+\lyxformat 508
 \begin_document
 \begin_header
+\save_transient_properties true
+\origin unavailable
 \textclass article
 \use_default_options true
 \maintain_unincluded_children false
@@ -9,16 +11,16 @@
 \language_package default
 \inputencoding auto
 \fontencoding global
-\font_roman default
-\font_sans default
-\font_typewriter default
-\font_math auto
+\font_roman "default" "default"
+\font_sans "default" "default"
+\font_typewriter "default" "default"
+\font_math "auto" "auto"
 \font_default_family default
 \use_non_tex_fonts false
 \font_sc false
 \font_osf false
-\font_sf_scale 100
-\font_tt_scale 100
+\font_sf_scale 100 100
+\font_tt_scale 100 100
 \graphics default
 \default_output_format default
 \output_sync 0
@@ -133,6 +135,10 @@ Drawing and contexts
 Methods that draw something (unless stated otherwise) require a valid rendering
  context.
  This context can come in three ways:
+\begin_inset Separator latexpar
+\end_inset
+
+
 \end_layout
 
 \begin_deeper
@@ -175,6 +181,10 @@ Non-negative numbers less than
 \end_inset
 
 )
+\begin_inset Separator latexpar
+\end_inset
+
+
 \end_layout
 
 \begin_deeper
@@ -195,6 +205,10 @@ Non-negative numbers less than
 \end_inset
 
  would be fully transparent.
+\begin_inset Separator latexpar
+\end_inset
+
+
 \end_layout
 
 \begin_deeper
@@ -316,6 +330,10 @@ n4 steelblue steelblue1 steelblue2 steelblue3 steelblue4 tan tan1 tan2 tan3
 
 \begin_layout Itemize
 The HSL base color names: hsl-<hue><saturation><lightness>.
+\begin_inset Separator latexpar
+\end_inset
+
+
 \end_layout
 
 \begin_deeper
@@ -339,6 +357,10 @@ The color names can have a modifier after space (multiple modifiers are
  allowed, separated by spaces): opaque10, opaque20, opaque25, opaque30,
  opaque40, opaque50, opaque60, opaque70, opaque75, opaque80, opaque90, opaque,
  hue{+,-}{1-23}, {saturation,lightness}{+,-}{1-16}.
+\begin_inset Separator latexpar
+\end_inset
+
+
 \end_layout
 
 \begin_deeper
@@ -451,6 +473,10 @@ addrobj: ADDRESS: The memory address.
 
 \begin_layout Itemize
 type: String: The type of data to map.
+\begin_inset Separator latexpar
+\end_inset
+
+
 \end_layout
 
 \begin_deeper
@@ -1373,6 +1399,10 @@ Load a palette from file <file> (resolved relative to <base>).
 
 \begin_layout Itemize
 The file format is a series of lines, each with following format:
+\begin_inset Separator latexpar
+\end_inset
+
+
 \end_layout
 
 \begin_deeper
@@ -1887,6 +1917,10 @@ h: number: The height of area to blit.
 \begin_layout Itemize
 ck: number: The color key.
  Pixels with this index are not copied.
+\begin_inset Separator latexpar
+\end_inset
+
+
 \end_layout
 
 \begin_deeper
@@ -1961,6 +1995,10 @@ vscl: number: Vertical scale factor (integer).
 \begin_layout Itemize
 ck: number: The color key.
  Pixels with this index are not copied.
+\begin_inset Separator latexpar
+\end_inset
+
+
 \end_layout
 
 \begin_deeper
@@ -2024,6 +2062,10 @@ h: number: The height of area to blit.
 
 \begin_layout Itemize
 operator: string: The operator to use.
+\begin_inset Separator latexpar
+\end_inset
+
+
 \end_layout
 
 \begin_deeper
@@ -2104,6 +2146,10 @@ vscl: number: Vertical scale factor (integer).
 
 \begin_layout Itemize
 operator: string: The operator to use.
+\begin_inset Separator latexpar
+\end_inset
+
+
 \end_layout
 
 \begin_deeper
@@ -2321,6 +2367,61 @@ Hashes bitmap <bitmap> and returns crypto-strong hash.
 Color order in bitmap is significant.
 \end_layout
 
+\begin_layout Subsubsection
+Method sample_texture: Sample a texture
+\end_layout
+
+\begin_layout Itemize
+Syntax: none bitmap:sample_texture(BITMAP source, number xx, number xy,
+ number x0, number yx, number yy, number y0, number scale, boolean wrap)
+\end_layout
+
+\begin_layout Standard
+Parameters:
+\end_layout
+
+\begin_layout Itemize
+source: BITMAP: The bitmap to sample
+\end_layout
+
+\begin_layout Itemize
+xx: number: s times the source x coefficient of target x axis.
+\end_layout
+
+\begin_layout Itemize
+xy: number: s times the source y coefficient of target x axis.
+\end_layout
+
+\begin_layout Itemize
+x0: number: s times the target x axis offset.
+\end_layout
+
+\begin_layout Itemize
+yx: number: s times the source x coefficient of target y axis.
+\end_layout
+
+\begin_layout Itemize
+yy: number: s times the source y coefficient of target y axis.
+\end_layout
+
+\begin_layout Itemize
+y0: number: s times the target y axis offset.
+\end_layout
+
+\begin_layout Itemize
+s: number: Scale of coordinates
+\end_layout
+
+\begin_layout Itemize
+wrap: boolean: If true, wrap the texture.
+ If false, read outside the texture as color 0.
+\end_layout
+
+\begin_layout Standard
+Samples the source as texture, performing linear transform (with nearest-neighbo
+r sampling) and writes the result to this bitmap.
+\end_layout
+
 \begin_layout Standard
 \begin_inset Newpage pagebreak
 \end_inset
@@ -2652,6 +2753,10 @@ h: number: The height of area to blit.
 \begin_layout Itemize
 ck: number: The color key.
  Pixels with this index are not copied.
+\begin_inset Separator latexpar
+\end_inset
+
+
 \end_layout
 
 \begin_deeper
@@ -2739,6 +2844,10 @@ vscl: number: Vertical scale factor (integer).
 \begin_layout Itemize
 ck: number: The color key.
  Pixels with this index are not copied.
+\begin_inset Separator latexpar
+\end_inset
+
+
 \end_layout
 
 \begin_deeper
@@ -2814,6 +2923,10 @@ h: number: The height of area to blit.
 
 \begin_layout Itemize
 operator: string: The operator to use.
+\begin_inset Separator latexpar
+\end_inset
+
+
 \end_layout
 
 \begin_deeper
@@ -2905,6 +3018,10 @@ vscl: number: Vertical scale factor (integer).
 
 \begin_layout Itemize
 operator: string: The operator to use.
+\begin_inset Separator latexpar
+\end_inset
+
+
 \end_layout
 
 \begin_deeper
@@ -3024,6 +3141,65 @@ hash: string: 64-hex digit hash
 \begin_layout Standard
 Hashes bitmap <bitmap> and returns crypto-strong hash.
  
+\end_layout
+
+\begin_layout Subsubsection
+Method sample_texture: Sample a texture
+\end_layout
+
+\begin_layout Itemize
+Syntax: none bitmap:sample_texture(BITMAP source, number xx, number xy,
+ number x0, number yx, number yy, number y0, number scale, boolean wrap)
+\end_layout
+
+\begin_layout Standard
+Parameters:
+\end_layout
+
+\begin_layout Itemize
+source: BITMAP: The bitmap to sample
+\end_layout
+
+\begin_layout Itemize
+xx: number: s times the source x coefficient of target x axis.
+\end_layout
+
+\begin_layout Itemize
+xy: number: s times the source y coefficient of target x axis.
+\end_layout
+
+\begin_layout Itemize
+x0: number: s times the target x axis offset.
+\end_layout
+
+\begin_layout Itemize
+yx: number: s times the source x coefficient of target y axis.
+\end_layout
+
+\begin_layout Itemize
+yy: number: s times the source y coefficient of target y axis.
+\end_layout
+
+\begin_layout Itemize
+y0: number: s times the target y axis offset.
+\end_layout
+
+\begin_layout Itemize
+s: number: Scale of coordinates
+\end_layout
+
+\begin_layout Itemize
+wrap: boolean: If true, wrap the texture.
+ If false, read outside the texture as color 0.
+\end_layout
+
+\begin_layout Standard
+Samples the source as texture, performing linear transform (with nearest-neighbo
+r sampling) and writes the result to this bitmap.
+\begin_inset Newpage pagebreak
+\end_inset
+
+
 \end_layout
 
 \begin_layout Subsection
@@ -3504,6 +3680,10 @@ unconvered: number: Number of bytes that were not converted (only if <success>
 \begin_layout Itemize
 error: string: Error that caused conversion to stop (only if <success> is
  false).
+\begin_inset Separator latexpar
+\end_inset
+
+
 \end_layout
 
 \begin_deeper
@@ -4121,11 +4301,19 @@ Calls function <fun> with function and specified arguments.
 
 \begin_layout LyX-Code
 on_paint = loopwrapper(function(wait)
+\begin_inset Separator latexpar
+\end_inset
+
+
 \end_layout
 
 \begin_deeper
 \begin_layout LyX-Code
 while true do
+\begin_inset Separator latexpar
+\end_inset
+
+
 \end_layout
 
 \begin_deeper
@@ -4884,6 +5072,10 @@ Set v' to <v>.
 
 \begin_layout Enumerate
 For each <q> q:
+\begin_inset Separator latexpar
+\end_inset
+
+
 \end_layout
 
 \begin_deeper
@@ -5839,6 +6031,10 @@ button_count (number): Number of buttons on controller
 
 \begin_layout Itemize
 buttons (array): Array of following info about each button:
+\begin_inset Separator latexpar
+\end_inset
+
+
 \end_layout
 
 \begin_deeper
@@ -5995,6 +6191,10 @@ Returns table of tables of all available keys and axes.
 
 \begin_layout Itemize
 value: Last reported value for control
+\begin_inset Separator latexpar
+\end_inset
+
+
 \end_layout
 
 \begin_deeper
@@ -8378,7 +8578,7 @@ Various callback-related functions.
 \begin_layout Subsection
 \begin_inset CommandInset label
 LatexCommand label
-name "sub:callback.register:-Register-a"
+name "subsec:callback.register:-Register-a"
 
 \end_inset
 
@@ -8415,7 +8615,7 @@ paint
 \begin_layout Subsection
 \begin_inset CommandInset label
 LatexCommand label
-name "sub:callback.unregister:-Unregister-"
+name "subsec:callback.unregister:-Unregister-"
 
 \end_inset
 
@@ -8443,7 +8643,7 @@ Syntax: function callback.<cbname>:register(function cbfun)
 Synonym for callback.register (section 
 \begin_inset CommandInset ref
 LatexCommand ref
-reference "sub:callback.register:-Register-a"
+reference "subsec:callback.register:-Register-a"
 
 \end_inset
 
@@ -8462,7 +8662,7 @@ Syntax: function callback.<cbname>:unregister(function cbfun)
 Synonym for callback.unregister (section 
 \begin_inset CommandInset ref
 LatexCommand ref
-reference "sub:callback.unregister:-Unregister-"
+reference "subsec:callback.unregister:-Unregister-"
 
 \end_inset
 
@@ -9049,6 +9249,10 @@ index: Index of button.
 
 \begin_layout Itemize
 type: Type of event, one of:
+\begin_inset Separator latexpar
+\end_inset
+
+
 \end_layout
 
 \begin_deeper
diff --git a/lua.pdf b/lua.pdf
index 7e9f685f..f7b35be0 100644
Binary files a/lua.pdf and b/lua.pdf differ
diff --git a/src/lua/gui-bitmap.cpp b/src/lua/gui-bitmap.cpp
index 67b3b332..902da8b3 100644
--- a/src/lua/gui-bitmap.cpp
+++ b/src/lua/gui-bitmap.cpp
@@ -536,6 +536,48 @@ namespace
 		}
 	}
 
+	template<typename pixel>
+	inline void _sample_texture(pixel* dest, uint32_t dwidth, uint32_t dheight, pixel* source, uint32_t swidth,
+		uint32_t sheight, int32_t xx, int32_t xy, int32_t x0, int32_t yx, int32_t yy, int32_t y0, uint32_t s,
+		bool wrap, pixel transparent)
+	{
+		int32_t th = s / 2;
+		size_t didx = 0;
+		for(int32_t i = 0; i < (int32_t)dheight; i++) {
+			int64_t ssx = (int64_t)xy * i + (int64_t)x0;
+			int64_t ssy = (int64_t)yy * i + (int64_t)y0;
+			for(int32_t j = 0; j < (int32_t)dwidth; j++) {
+				//Compute whole and fractional parts.
+				int64_t isx = ssx / (int32_t)s;
+				int32_t fsx = ssx % (int32_t)s;
+				int64_t isy = ssy / (int32_t)s;
+				int32_t fsy = ssy % (int32_t)s;
+				//Make the fractional parts always positive.
+				if(fsx < 0) { fsx += s; isx--; }
+				if(fsy < 0) { fsy += s; isy--; }
+				//Round the whole parts.
+				isx += fsx > th;
+				isy += fsy > th;
+				//Compute color.
+				pixel p = transparent;
+				if(wrap) {
+					isx = isx % swidth;
+					if(isx < 0) isx += swidth;
+					isy = isy % sheight;
+					if(isy < 0) isy += sheight;
+					p = source[isy * swidth + isx];
+				} else if(isx >= 0 && isx < swidth && isy >= 0 && isy < sheight) {
+					p = source[isy * swidth + isx];
+				}
+				dest[didx] = p;
+				//Update values for next pixel.
+				ssx += (int64_t)xx;
+				ssy += (int64_t)yx;
+				didx++;
+			}
+		}
+	}
+
 	inline int64_t mangle_color(uint32_t c)
 	{
 		if(c < 0x1000000)
@@ -739,6 +781,7 @@ namespace
 		{"blit_porterduff", &lua_bitmap::blit<false, true>},
 		{"blit_scaled_porterduff", &lua_bitmap::blit<true, true>},
 		{"save_png", &lua_bitmap::save_png},
+		{"sample_texture", &lua_bitmap::sample_texture},
 	}, &lua_bitmap::print);
 
 	lua::_class<lua_dbitmap> LUA_class_dbitmap(lua_class_gui, "DBITMAP", {
@@ -758,6 +801,7 @@ namespace
 		{"blit_scaled_porterduff", &lua_dbitmap::blit<true, true>},
 		{"save_png", &lua_dbitmap::save_png},
 		{"adjust_transparency", &lua_dbitmap::adjust_transparency},
+		{"sample_texture", &lua_dbitmap::sample_texture},
 	}, &lua_dbitmap::print);
 }
 
@@ -1088,6 +1132,21 @@ int lua_bitmap::save_png(lua::state& L, lua::parameters& P)
 	}
 }
 
+int lua_bitmap::sample_texture(lua::state& L, lua::parameters& P)
+{
+	lua_bitmap* src_p;
+	int32_t xx, xy, yx, yy, x0, y0;
+	uint32_t s;
+	bool wrap;
+	uint16_t trans = 0;
+
+	P(P.skipped(), src_p, xx, xy, x0, yx, yy, y0, s, wrap);
+
+	_sample_texture(pixels, width, height, src_p->pixels, src_p->width, src_p->height, xx, xy, x0, yx, yy, y0,
+		s, wrap, trans);
+	return 0;
+}
+
 /** DBITMAP **/
 lua_dbitmap::lua_dbitmap(lua::state& L, uint32_t w, uint32_t h)
 {
@@ -1288,6 +1347,19 @@ int lua_dbitmap::adjust_transparency(lua::state& L, lua::parameters& P)
 	return 0;
 }
 
+int lua_dbitmap::sample_texture(lua::state& L, lua::parameters& P)
+{
+	lua_dbitmap* src_p;
+	int32_t xx, xy, yx, yy, x0, y0;
+	uint32_t s;
+	bool wrap;
+
+	P(P.skipped(), src_p, xx, xy, x0, yx, yy, y0, s, wrap);
+
+	_sample_texture(pixels, width, height, src_p->pixels, src_p->width, src_p->height, xx, xy, x0, yx, yy, y0,
+		s, wrap, framebuffer::color());
+	return 0;
+}
 
 template<bool png> int lua_loaded_bitmap::load(lua::state& L, lua::parameters& P)
 {